The Nashville Serial Killer

[JiM]

Hi there !
Here is another design of mine, made a few years ago during a discussion over at TDPRI. It's meant to add series wirings to a Nashville-type Telecaster, thus providing killer hi-gain tones. It requires a 5-way Superswitch, and some kind of DPDT (can be a push-pull pot).
I did not build it, as my Tele is not a Nashville-type, and i don't have a SSS-equipped guitar. A HSH version is in the works, though.



The parallel mode provides what you'd expect from a Nashville Tele, i.e. like a standard Tele plus the parallel positions of a Strat. The series mode provides the same in series, but in reverse order. This may seem to be a problem, but it should actually be quite useful, in order to provide more contrast at the flick of one switch. Four out of the six dual-pickup positions will be hum-cancelling, depending on which coils are RWRP. There is no middle pickup alone, but who uses it anyway ?

An optional addition is a couple of resistors which end up in parallel with the volume pot, to fake a 250k pot in parallel mode for a bit less brightness, and less redundancy in positions 1 and 5. This may mess a little with the pot taper as well.
I did not draw a wiring diagram, as it would be quite messy and depend a lot of the type of Superswitch you have (PCB-based or Fender-style).
Yup, no terminal left open !

[ashcatlt]

Jun 8, 2014 7:48:25 GMT -5 JiM said:

Yup, no terminal left open !

But only because you used a couple of them to make redundant connections. That's cheating.

What's with the resistors between the pickups? They can't possibly be essential to the workings, and I'd imagine would cause more harm than good. Interested to hear your reasoning, though.

[JiM]

Jun 8, 2014 10:10:31 GMT -5 ashcatlt said:

But only because you used a couple of them to make redundant connections. That's cheating.

Could you please point which ones are truly redundant ? When designing it, i remember needing all of those in one mode or the other, sometimes only for shorting a coil. But less connections means less soldering to do, and that would be a good thing.

One example : the link shorting the Middle pickup in position 3 may seem redundant in parallel mode, but it's important in series mode. Otherwise you would have N*M*B there.

Jun 8, 2014 10:10:31 GMT -5 ashcatlt said:

What's with the resistors between the pickups? They can't possibly be essential to the workings, and I'd imagine would cause more harm than good. Interested to hear your reasoning, though.

As i said, those are optional, and they are shorted in series mode.
You know, a guitar pickup's resonance is shifted depending on the load provided by the volume and tone pots, usually people prefer 500k with humbuckers and 250k with single coils. I've drawn the schematic with 500k pots, for a balanced tone in series mode, but this may be a bit too bright in parallel mode for some people. Either one of those resistors end up wired in parallel with the volume pot in parallel mode, faking a 250k pot. Alternatively, you could use 250k pots, forget those resistors, and live with a series mode a bit dark sounding.

After looking more closely at it, here is what happens in parallel mode :

1. Neck pickup in parallel with 235k (both resistors)
   
2. Neck and Middle pickups in parallel with 470k
   
3. Neck and Bridge pickups in parallel with 940k (both resistors in series)
4. Middle and Bridge pickups in parallel with 470k
   
5. Bridge pickup in parallel with 235k

Let's pretend that it's an automatic adaptation of the load impedance, depending on which coils are selected